Frame Welding : The Complete Guide [2023]

The welding method used to repair frames of trucks, cars, or any sort of automobile is known as frame welding.

All the vehicles which are continuously operated need constant maintenance. The frames particularly are subjected to different forms of pressure. 

There are several welding techniques used in frame welding, a couple of questions might pop up in your mind. 

Does welding a frame weaken it?

Is Frame Welding Illegal?

Don’t worry! In this article, we are going to focus on how frame welding works, different methods used in it, how to weld frames of trucks, bike, bicycle, etc, and the cost to do so. Also, we are going to cover some FAQs for YOU.

Frame Welding being done on a Truck's Frame
Frame Welding of A Truck

Frame Welding Methods

Frame Welding is a pseudo name given to the welding of frames in which many different welding processes can be used. 

Since the weld joints need to be long-lasting, choosing methods should be carefully done.

The following are the welding methods used : 

MIG Welding 

MIG stands for Metal Inert Gas Welding, also known as wire feed welding, If you have some welding knowledge, you may have already heard about it. 

It is an arc process, in which an electrode wire is fed into the weld pool via the help of a welding gun resulting in the weld joint. 

To ensure there is no environmental contamination, Shielding gases are used to protect the weld.

MIG Welding can be used in automotive crack repairs, fabrications, and robotics.

TIG Welding

Compared to MIG, TIG ( Tungsten Inert Gas) requires some level of expertise to work with. 

Also known as the GTAW ( Gas Tungsten Arc Welding), doesn’t require any filler materials. 

A non-consumable tungsten electrode is used, which melts the metal to form a joint between them. 

Shielding Gas is also utilized in TIG Welding.

Not such a beginner-friendly method, as any mistake in the weld, could cause damages to parts. 

You have to make sure that there is no dirt or rust on the materials used, the presence of these could significantly increase the formation of cracks in the future.

However, TIG Welding is still majorly used in automobile manufacturing industries.

Laser Beam Welding

This welding technique uses lasers to join metal or thermoplastics together. 

Relatively newer method compared to other welding methods, Laser Beam Welding uses Lasers as the heat source by concentrating the beam. 

This process is frequently used nowadays in automotive industries as the weld made is of very high quality. 

In addition, the initial cost as well as the maintenance cost is lower than other welding machines and methods.

Friction Welding

In friction welding, the heat is generated mechanically and not via any external sources. Pressure and speed are utilized to join metal together.

The two metal parts slide against each other generating heat due to friction. 

Further, the metals are held under pressure. The speed, pressure, and friction are controlled by a friction welding machine.

Used in the automotive industries, mainly in the manufacturing of engine valves, piston rods, etc.

Resistance Spot Welding

The underlying principle of Resistance Spot Welding is the generation of heat from the resistance between the metal parts by the flow of electric current through them.

Copper electrodes are used to run an electric current through the metal parts, which results in resistance between the parts. 

Heat is generated in the process and the parts are held together by applying pressure.

This welding method is widely used across automotive industries but may result in some inconsistencies as it limits the spots since the workpiece can be overlapped.

Medium Frequency Welding

Using the principle of resistance spot welding, it uses AC current which is supplied through an inverter. 

The inverter converts the current into a medium frequency and then passed into the welding gun via a transformer.

In the automotive industry, these are regularly used since the welds made are lightweight and more cleaner.

Frame of Bike -Bike Frame Welding
Frame of A Bike – After Frame Welding is Done

Problems With Frames

So you have got the basic idea of how to weld frames. 

But there are many problems faced when welding frames, some of them are minor while others can be critical.

In Automotives we should also look out for the weight, any unnecessary welds can increase the total weight of the vehicle due to the addition of welded metal. 

This reduces fuel efficiency in the long run.

Major problems are bends and cracks on the frames of trucks and cars, which leads to the need frame welding. 


Repeated overloading of the vehicle can cause bends, these are sometimes permanent damages. Bent frames can be often seen in vehicle accidents. 

Fixing serious frame bents are expensive, as frame welding experts are required to work upon these issues.


A line on the surface of the vehicle which is split apart, but is not completely separated are known as cracks. 

Cracks can be complete nuisances and require heavy work to fix them. 

There are several reasons based on which cracks can be developed on vehicle surfaces. 

Causes Of Cracks

There can be cracks in other parts of the vehicle as well. But since we are strictly discussing frame welding, we will stick to cracks on the frames.

Cracks are developed mainly due to overloading or fatigue. 

For example, a shock from a pothole in the road can cause stress on the suspension as well as the frames. 

Talking about fatigue, all metals have a definite number of times until which they can be stressed. This number is called the stress cycle of that metal. 

However, the frames are made using a combination of metals and it becomes difficult to accurately calculate the stress cycle.

Cracks can sometimes be small, if a vehicle has gone past its stress cycle cracks will start to appear frequently. 

And delaying the repair can cause further harm to the vehicle resulting in permanent damages. 

Frame Welding Legal Issues

Well if you have decided to weld frames of your truck or car, you must also know the legalities related to it. 

We can divide the legalities related to welded frames into two parts :

  1. Using a vehicle with a welded frame on the highway
  2. Selling a vehicle with a welded frame

 Using A Vehicle with A Welded Frame On The Highway

The FMCSA (Federal Motor Carrier Safety Administration) 49th article(49 CFR § 393.201 – Frames) states that “no holes shall be drilled in the top or bottom rail flanges, except as specified by the manufacturer,”

Frame welding includes drillings, cuts, splicing, and welds, and thus is considered as a violation of FMCSA code. 

Therefore, it is illegal to use them on public highways and are restricted to private spaces.

Even though it is highly unlikely to get caught, if you are caught with illegitimate welded frames, it can lead to serious repercussions like penalties or hefty fines.

Adding to that, in the event of an accident the frame weld is traced back to the person who welded it and may get charges pressed against them. 

Creating complications further, insurance companies revoke insurance due to welded frames.

Selling A Vehicle with A Welded Frame

Frame Welding is not essentially illegal, and the same goes for the vehicle sold which has welded frames. 

However, there is a factor of safety linked with welded frames. 

Since frames are considered the skeleton of a vehicle any discontinuity or any problem can cause harm. 

Thus, it is somewhat on the lines of unlawfulness to sell a vehicle with welded frames.

It is a good practice to give a written document which clearly states that the vehicle consists of a welded frame. 

In the event of a legal dispute, the signed document will be a major help for both the buyers’ side and the sellers’ side.

Welding A Car Frame
Car Frame Welding

Frame Welding Procedure

I will show you the exact procedure to go by if you want to weld the frame of your truck, motorcycle, car, etc. 

Point of caution: If you are not an experienced welder, try to avoid welding on your own as any misstep can cause serious irreparable damages to the frame

Firstly, Locate the crack. 

Look out for visible cracks or bending on the frame, check the alignment of the car. If even after the wheel alignment is done, check whether your car is slightly tilted.

Cracks create noises, hear out from where a squeaking noise is coming from. 

If you have located the crack, your first step is successfully done.

Now, check how deep the crack is. Sometimes, small cracks can be fixed with the help of braces. 

If the crack is big and causing issues to the vehicle, It should be spliced as soon as possible via the means of welding. 

Now for welding the parts together, make sure that the base metals are clean. Any form of rust or contaminants may result in a negative impact after welding.

Choose any welding method from above which you are comfortable in and weld it together. 

After you are done with the process, quickly check for any visual signs of a bad weld.

Don’t forget to wear your safety equipment to avoid any welding mishaps.

If you are a novice in Frame welding, it is strictly suggested to visit a frame welding shop or seek the help of a professional.

Truck Frame Welding

Trucks are huge, and so is the work involved. 

They carry around materials weighing hundreds of kilos for thousands of miles. And somewhere between these transporting, they develop cracks.

To fix the crack, It is either annealed or spliced together by welding. 

The sooner the splicing is done the better it is for the truck. Once the frame reaches the stress cycle it starts developing cracks at a faster pace.

If the cracks are still caused after welding, the process of annealing can be used. 

In annealing, the component is slowly heated to elevated temperature and held there for a long period and cooled. 

It relieves stress caused by welding or other such processes.

However, fixing the frame of a truck is not as easy as it sounds. It requires expertise and experience in the field of frame welding to fix it properly.

It is also not safe to weld a truck frame, as it can negatively impact the frame by developing more cracks or weakening of the frame. 

A strong frame is the underlying strength of the truck and consequently any harm to it will cause serious damages.

Bike Frame Welding

Similarly, bikes can have cracks on their frames too. Hence, bike frames are welded as well to treat the cracks.

For fixing the bike frame, you have either go by brazing or by welding methods such a TIG or MIG.

How do I choose which welding method to use for my bike frame?

Using welding for Bike frames would be ideal if you have a low budget and time. 

On the other hand, brazing is expensive and takes more time to complete the work. But the quality of the work in the cases of bikes goes for brazing. 

If your bike is made of aluminum, you need to make sure that the frame is heat-treated or annealed to fix any distortions present in them.

Technicalities of Frame Welding

Since frame welding requires a great level of expertise, there are many technicalities you should look out for such as :

Lack of Penetration: A truck frame or an automobile frame is one solid piece of metal. The presence of multiple welds across its frame which are joined only at the surface and not joined completely may lead to more stress over the frame.

Having Control over the Welding Gun: If you use welding to fix the frame avoiding any distortion is good for the frame, since weak distorted weld will further weaken the frame.

Cleaning of the Frame: The frame should be clean and free from any form of contaminants, thus should be thoroughly cleaned. Failure to do so might result in weak welds or corrosion in the future.

Using High-Quality Material: It is advised to use high-quality materials for welding. Since the frame is the backbone of a vehicle and the strength of it depends upon the frame. Cheaping out on the materials can cause long term issues.


How much would Welding a Truck Frame Cost?

The total cost of fixing or welding the frame of a truck depends upon the condition of the frame. The cost may be in the range of $5000 to $10000.

What MIG Wire for Welding Car/Truck frame?

Usually, .030” or .035” mild steel wire plated with copper is the preferred MIG wire for welding car frames. This also depends upon the welder.

Which is Better for Frame Welding, TIG or MIG?

TIG welding is considered better for frame welding as it is easier to work with and gives control over both current and metal deposition rates. But knowing what you are doing is very important as well.

Should I Weld Vertically or Horizontally in Frame Welding?

It is a good practice to weld vertically in frame welding particularly since they reduce the chances of crack development in the future significantly.


In this article, I tried to briefly explain how frame welding works.

You should make sure that you are well versed in the methods before jumping straight into welding frames.

It is usually better to leave this work for professionals if you are just starting out.